I am curious to know if any readers have bought groceries online through Amazon. Do many people know you can do that via Amazon?

A straw poll among my colleagues and friends resulted in blank looks – while Amazon was the first name many mentioned for books and DVDs, food did not have the same instinctive association.

The world’s largest online retailer launched its groceries range, including pasta, tea and chocolate, in Britain in July 2010 with 22,000 products.

It was expected to shake up the grocery market in the same way it has cuckoo-kicked its way into music and books, but three years later the food arm of the business appears to be lying quiet.

Amazon Grocery has dramatically expanded its range, now selling around 200,000 items, ranging from niche and ethnic foods to everyday products such as nappies, washing powders and pet food. The products are typically sold in bulk.

When I checked, the total cost of the items on Amazon.co.uk was £39.86; the estimated cost of posting and packaging was £7.74.

The items would have been dispatched separately by different sellers and the goods were scheduled to arrive in the post within three to five days, using standard delivery. I could get them delivered sooner at additional cost – opting for express delivery would have raised the postage and packaging charges to £14.94.

On Sainsbury’s, the same quantities of the same items cost £32.84, with a £6.95 delivery charge because my order was less than £40.

These items could be delivered in a one-hour time slot of my choosing.

A spokesman for Amazon said the retailer did not envisage that customers would currently undertake a traditional weekly shop at the Amazon Grocery store.

“We have created a store that includes not only a great choice of household favourites but also a large selection of international, niche and ethnic foods, many of which may have proved hard to find for shoppers in the past,” she said.

But iIndustry experts point out that while Amazon might not be making much noise in the grocery market now, it may be only a matter of time.

The stated aim of Amazon is to “be the place where you can find and buy virtually anything online” and it has the advantage of its distribution network – including eight fulfilment centres in Britain – which means it can deliver anywhere in the country.

Clive Black, an analyst at stockbrokers Shore Capital, said: “Amazon has a market-busting proposition in music and books. It has deep pockets and patience, so you shouldn’t write it off in the long term.”

John Coll, a director of consumer insight firm Kantar Worldpanel, said: “Twenty years ago Tesco and Sainsbury’s stretched beyond food. We are now seeing that in reverse as Amazon stretches into food. It is just a matter of time, because the momentum is clearly behind online shopping.”

Online business accounts for just £6.5bn, or 4pc, of Britain’s £169.7bn grocery market, but it is growing rapidly. Figures out this week from IGD, a food and consumer goods charity, showed that online sales were set to grow by 124pc over the next five years, far outstripping the growth of supermarkets.

James Foord of the shopping comparison site mySupermarket said he saw Amazon as the “biggest competitor threat” in the online grocery market in future. “The shift to smartphone use makes them particularly threatening,” he said. “Physical stores are no longer a necessity.”

Mr Black said he expected Amazon to edge its way slowly into the grocery market as the retailer experimented with different formats.

It would be foolish to underestimate the ambitions of the online retailer.

Its fledgling food business in the US, Amazon Fresh – which delivers products ranging from milk to digital cameras using its own vans – is expanding from its home city of Seattle to Los Angeles and could launch in 20 other urban areas in the next year.